you certainly have the right idea, but ill give you some help as it takes context clues to put this together (Including twitter posts and weird expanded universe around the game so its not the easiest thing to pick up), some pets are smarter then others, some more advanced, and each has a unique set of qualities to them. Some can communicate openly, some can't. Some may understand English, but can't speak it. However they may be able to communicate in English but not through the usual method. Their is an order and symbolism behind language in this game. For example, the most powerful pets can be HEARD speaking. The second most can be seen speaking English. So...if you come across someone not speaking clearly or communicating clearly, you can presume they are potentially weak OR they were never intended to communicate as it was deemed unnecessary for them to be able to do so. This to however, has implications in the reality of the game.
perhaps! Though, as time passes, those creatures may learn to speak, and history may blur, people will remember pets being there that weren't. or not remember certain pets being there before...you may even think some pets are talking differently then before O.O I try to leave room in every game for them to breathe in the future, if it seems viable.
I have seen it live streamed, but by someone who was totally new to it, so it was a sort of crowd sourcing for answers situation, and that was very interesting. (and super informative to me, and led to several fixes and updates) If 'im being totally honest, id be honored if you chose to do that, but would very much leave it up to you. It has the appeal of being free, so any one who showed interest would be welcome to poke around in it themselves. There's Multiple endings, so if you think you have an audience that might enjoy you poking around to find more, then i think it could lend itself again to have people saying try this and try that. Not to mention, they could join you in playing and perhaps discover things you haven't. But in total honesty, and transparency id say Yes,but only if you think their might be more you haven't discovered, such as, the game has multiple endings with a view of the outside world. I tried my best to layer this game with replay value.